Method for highly exothermic epoxidation reactions

Abstract

A process is provided for the production of oxirane compounds by reaction of an olefin such as propylene with an organic hydroperoxide using a solid contact catalyst, characterized in that a series of separate reaction zones are used, each packed with epoxidation catalyst, and the concentration of hydroperoxide in the feed to each reaction zone is maintained below 8 wt %.

I claim:  
     
       1. In a process for the catalytic liquid phase exothermic reaction of a C 3 -C 5  olefin with an aryl alkyl hydroperoxide which comprises passing a mixture containing the olefin and hydroperoxide at reaction conditions of elevated temperature and pressure through a series of separate reaction zones each packed with a bed of solid epoxidation catalyst, the improvement wherein the liquid reaction mixture from the first reaction zone is divided into a first stream which is recycled to the first reaction zone and preheats the net feed thereto and a second stream which passes to the second reaction zone and is further reacted therein, the hydroperoxide concentration in the feed to each reaction zone being less than 8 wt %. 
     
     
       2. The process of  claim 1  wherein propylene and ethylbenzene hydroperoxide are reacted to form propylene oxide. 
     
     
       3. The process of  claim 1  wherein the solid catalyst is a titania on silica catalyst. 
     
     
       4. In a process for the catalytic liquid phase exothermic reaction of a C 3 -C 5  olefin with an aryl alkyl hydroperoxide which comprises passing a mixture containing the olefin and hydroperoxicde at reaction conditions of elevated temperature and pressure through a series of separate reaction zones each packed with a bed of solid epoxidation catalyst the improvement wherein only a portion of the total hydroperoxide is fed to each reaction zone whereby the hydroperoxide concentration in the feed to each reaction zone is less than 8 wt %.